In recent years, there have been growing interests in the global warming and the energy problem, and needs for a technology for reducing power consumption have been increasing. An electronic device for daily use in which power consumption is reduced without loss of convenience has been actively developed.
Reducing power consumption of an electronic device is important not only in a period during which the electronic device is operated but also in a period during which the electronic device is not operated. In other words, it is important to reduce power consumption in a standby state (hereinafter referred to as standby power).
In view of the problem of a reduction in standby power, Patent Document 1 focuses on a multi-tap that is a power supply control device and discloses the multi-tap in which a CPU (central processing unit), one of data processing devices, is provided. Patent Document 1 discloses a structure in which power supply is controlled in accordance with a status of use of an electronic device with the use of the CPU provided in the multi-tap.